o2 sensor questions

Average life span was 60K miles.

The sensor does wear out. In early 80's MB's, they built a switch into the odometer to activate the O2 sensor light at approx 60K miles and there was no reset, so servicing involved replacing the sensor and REMOVING the warning bulb from the instrument cluster. A failed sensor in a Bosch CIS system would result in "limp home" mode and the car would run very rich, not lean.

With upgrades in the monitoring systems, the O2 sensor light became resettable and part of the OBD codes.

I recently changed the original sensor of my 230E 92, with 90k miles. Idle, acceleration and emissions improved. The most interesting effect however, was on fuel economy, it improved near 7%, in my case enough to amortize the sensor cost within a year. I did it myself with a special wrench.

"jb" escribió en el mensaje news:qtseg.41306$ snipped-for-privacy@tornado.ohiordc.rr.com...

re replacements.... I tried to attribute engine performance woes to my oxygen sensor since it was 250k km old. wisdom is to replace around 100k km. I learned how to test and found my sensor to be just fine... Turned out my problems were caused by the electric fuel distribution valve (EHA??) as well as the oil seals. So, O2 sensors can last a long time

cheers, guenter